Cytoprotective effects of endothelin-1 on mesenchymal stem cells: an in vitro study

Stem cell-based therapies is a promising approach for regenerative therapy in various diseases. Some obstacles remain to be solved before clinical application of the cell therapy is realized, including increasing the survival of transplanted stem cells, reducing loss of transplanted cells, and maintaining adequate vascular supply. Recently, stem cell preconditioning with chemical and pharmacological agents has been shown to increase therapeutic efficacy. The present study investigated the effect of endothelin-1 (ET-1) on survival, angiogenesis, and migration of mesenchymal stem cells (MSCs), in vitro. MSCs were treated with various concentrations of ET-1 and the expression of cyclooxygenase-2 (COX-2), hypoxia-inducible factor-1 (HIF-1), C-X-C chemokine receptor type 4 (CXCR4), C-C chemokine receptor type 2 (CCR2), vascular endothelial growth factor (VEGF), angiopoietin-2 (Ang-2), angiopoietin-4 (Ang-4) and matrix metalloproteinase-2 (MMP-2) were examined. Caspase 3 activity and prostaglandin E2 (PGE2) were determined by ELISA assay. MSCs migration and tube formation potential were assessed using scratch test and three dimensional vessel formation assay. ET-1 enhanced the MSCs viability. In ET-1- treated MSCs, expression of COX-2, HIF-1, CXCR4, CCR2, VEGF, Ang-2, Ang-4 and MMP-2 were increased compared to control groups. Elevation of all these genes were reversed by celecoxib (50 μmol/L), a selective COX-2 inhibitor. PGE2 generation, MSCs migration and tube formation were enhanced by ET-1 conditioning, whereas caspase-3 activity was reduced in these cells, compared to the control group. The results presented here reveal that preconditioning of MSCs with ET-1 has strong cytoprotective effects through activation of survival signalling molecules and trophic factors.